Micro-components comprise such components as: semiconductor devices, such as integrated circuits; optoelectronic components, such as laser diodes; and optical components, such as mini-lenses, which are typically mounted on a substrate, such as a circuit board. Operating performance for these micro-components can vary as a function of temperature, and these micro-components often require heat dissipation and/or cooling elements to maintain the micro-components within a desired operating temperature range. To provide a properly functioning micro-component, the operating temperature range must be known and controlled. While excessively high temperature conditions may cause performance problems of individual micro-components, operating temperatures that are too low can also adversely affect performance.
In addition to performance variations of a micro-component based on its temperature, the performance of a micro-component can also vary when the substrate temperature varies from a desired operating temperature. Variation in the substrate temperature from the desired operating temperature results in thermal expansion and contraction causing dimensional variations of the substrate. Moreover, these dimensional substrate variations cause a variation in the relative locations of the components mounted on the substrate. Consequently, control of the substrate temperature is desired.
A semiconductor laser diode (herinafter “laser diode”) converts electrical data signals into optical data signals. Several important laser diode operating parameters change as a function of temperature, resulting in poor performance if operated outside of its desired operating temperature range. Often, laser diodes operate in an environment that is too cold. These low temperatures cause performance problems and require additional heat to bring the laser diode to a desired temperature. Therefore, heating the laser diode is desired, and cooling is not necessary.
Thermoelectric (TE) devices are well known and used in the electronics industry to both heat and cool micro-components. However, for micro-components requiring only heating, such functionality is not necessary. For such applications, TE devices are costly and consume valuable real-estate on circuit boards. Furthermore, maintaining the micro-components within an appropriate operating temperature by cooling with TE devices generates waste heat energy resulting in a loss of efficiency.